The present experiment was set-up to appraise protective role of ALA in sunflower cultivars (FH-1581 and FH-1572) under water scarcity stress. The ameliorative role of ALA in sunflower under water stress is not fully understood. Results showed significant decline in growth parameters, ascorbic acid and chlorophyll but marked increase in MDA, H₂O₂, total soluble proteins, flavonoids, proline, phenolics, total free amino acids as well as enzymes activities namely CAT, POD and SOD in plants under water scarcity. ALA application reduced oxidative damage by lowering H₂O₂ and MDA contents. ALA application differentially affected two cultivars under stress. Higher biomass accumulation was manifested in cv. FH-1581, while cv. FH-1572 was inferior in this context. Greater drought tolerance in cv. FH-1581 was related to higher cellular levels of proline, total free amino acids and efficient antioxidant system.

中文翻译：

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外源施用 5-氨基乙酰丙酸调节向日葵在水分亏缺胁迫下的生长、次生代谢和氧化防御。


本实验旨在评估 ALA 对向日葵品种（FH-1581 和 FH-1572）在缺水胁迫下的保护作用。 ALA 对向日葵在水分胁迫下的改善作用尚不完全清楚。结果显示，植物的生长参数、抗坏血酸和叶绿素显着下降，但 MDA、H ₂ O ₂ 、总可溶性蛋白、类黄酮、脯氨酸、酚类、总游离氨基酸以及酶活性（即 CAT、POD 和 SOD）显着增加在缺水的情况下。 ALA的应用通过降低H ₂ O ₂和MDA含量来减少氧化损伤。 ALA 的应用对胁迫下的两个品种产生了不同的影响。较高的生物量积累表现在cv中。 FH-1581，而CV。 FH-1572 在这方面表现较差。 CV 具有更强的耐旱性。 FH-1581 与较高的细胞水平的脯氨酸、总游离氨基酸和高效的抗氧化系统有关。